There is a related art vehicle seat in which the supporting surface is formed of a planar elastic body. For example, Patent Document 1 discloses a net seat for a vehicle. In the net seat disclosed in Patent Document 1, a net is attached to a seat frame by hooking a hook of substantially J-shaped cross section sewn to an end of the net on a wire provided at the seat frame. In such a net seat, a variation in the stretching state of the net may occur due to variation in the sewing position of the hook.
In addition, as a net seat which is not used for a vehicle, but used in an office etc., there is a related art net seat in which a resin frame body is integrally formed at the periphery of a net and the entire periphery of the resin frame body is attached to a pipe frame to form a supporting surface (for example, refer to Patent Document 2). In such a net seat, the net is previously supported on the frame body in a stretched state by molding a resin frame body at the periphery of the net in a state in which the net is stretched in a die and mold. And, in this state, the frame body is attached to the seat frame, thereby the stretching state of the net is difficult to vary.    Patent Document 1: JP-A-2002-233437    Patent Document 2: JP-A-2004-90521